Comparison of Ropivacaine Plus Dexmedetomidine and Ropivacaine Plus Magnesium Sulfate Infiltration for Postoperative Analgesia in Patients Undergoing Lumbar Spine Surgeries

Background: Acute pain after lumbar spine surgery is due to soft tissue and muscle separation at the operation site. Local anesthetic wound infiltration is a safe and effective method for postoperative analgesia following lumbar spine surgery. In this study, we aimed to investigate and compare the efficacy of ropivacaine plus dexmedetomidine and ropivacaine plus magnesium sulfate for postoperative analgesia in lumbar spine surgeries.Materials and method: This prospective randomized study was conducted on 60 patients, aged between 18 and 65 years, either sex, American Society of Anesthesiologists classification I and II patients scheduled for single-level lumbar laminectomy. Patients were randomly allocated into two groups 30 patients each. Twenty to 30 minutes before skin closure and after hemostasis was achieved, the surgeon infiltrated 10 mL of study drugs into paravertebral muscles on each side. Group A received 20 mL of 0.75% ropivacaine plus dexmedetomidine and group B received 20 mL of 0.75% ropivacaine plus magnesium sulfate. Postoperative pain was assessed by the visual analog scale at 0 minute (immediately after extubation), 30 minutes, 1st hour, 2nd hour, and thereafter at 4th hour, 6th hour, 12th hour, and 24th hour. Time to rescue analgesia, total analgesic consumption, hemodynamic variables, and complications if any were recorded. Statistical analysis was done using SPSS version 20.0 (Armonk, NY: IBM Corp.).Results: The time to first requirement of analgesia in postoperative period was significantly longer in group A (10.05 +/- 1.62 hours) than in group B (8.07 +/- 1.83 hours) (p < 0.001). Total analgesic consumption was significantly higher in group B (197.50 +/- 36.76 mL) compared to group A (142.50 +/- 22.88 mL) (p < 0.001). Heart rate and mean arterial pressure were significantly lower in group A compared to group B (p < 0.05).Conclusion: Local infiltration of surgical site with ropivacaine plus dexmedetomidine provided better pain control than ropivacaine plus magnesium sulphate infiltration and is safe and effective analgesia for patients undergoing lumbar spine surgeries in postoperative period.